Owing to introduction of a multi-node system, various communication techniques have become available, thereby improving channel quality. However, a new control channel is required to apply Multiple-Input Multiple-Output (MIMO) and Coordinated Multi-Point (CoMP) to the multi-node environment. In this context, Enhanced-Physical Downlink Control Channel (EPDCCH) is under discussion and it is regulated that the EPDCCH is assigned to a data region rather than a legacy control region (hereinafter referred to as a PDCCH region). Consequently, since the EPDCCH enables transmission of control information for a node to each UE, lack of the legacy PDCCH region may be solved. For reference, the EPDCCH is not provided to legacy UEs and only LTE-A UEs can receive the EPDCCH.
In this environment, for EPDCCH link adaptation, channel state of the EPDCCH needs to be reported.